Why Did MPI put boost pressure to both sides of the BOV when the BOV instructions say to Venbt the top to the atmasphier? and put a brass T valve in line to the top side?

Why Did MPI put boost pressure to both sides of the BOV when the BOV instructions say to Venbt the top to the atmasphier? and put a brass T valve in line to the top side?

Go over and ask on the dd forum there are alot of twin guys there whenever I had a question about setting up my twins I got alot of help.

It shouldn't say to vent to atmoshpere. It's a wastegate not a BOV BTW. BOV's are on the intake side and wastegates are on the exhaust side. I haven't looked at the instructions for some time but for max/highest boost the unregulated air should go to the top of the wastegate (the furthest away from the hot pipe) and the regulated air should go to the bottom with the valve shut. I generally leave the valve slightly open as it is easier on the wastegate.

Good lord I know better BOV WTH =) Its a WG I know that hehe Im mental sometimes. I was trying to order 45* fittings when I knew I wanted 90*s.
Anyways Thanks My WG Instructions said vent to at.
I still dont undersand why we are putting pressure on both sides of the diaphram Unless im nmissing somehing

Adding air to the top acts like a heavier spring. Adding less air to the bottom lessens the effect of the air going to the top or like a somewhat lighter spring. I'm not sure which gate you have but the Tial gates don't like a lot of air on one side and nothing on the other because it rips the diaphram after awhile. The early JGS gates had diaphrams as well and while they tend to be better they will still rip. The later JGS gates have o-rings and can handle no boost on one side better because there is no diaphram to tear.

Ok so i did some testing by using regulated air to both sides of the W/G as well as top side then bottom side. Here is my results, with any pressure setting T'd to top and bottom of Waste Gate it does not open. With it T'd and neddle valve on bottom it opens for a second then closes longer depending on how far open the needle valve is closed ( point is it will not open with ANY pressure on both sides) pressure on the bottom the waste gate opens, pressure on the top and it does nothing but leak air.
Unless im totally missing something here, when you t boost pressure to both sides of the waste gate you do nothing so take it off plug the holes and throw it in the trash? this is not a flame thread Im just stating what I see and am just wondering if im just completly retarded :(

Double clicked smehowe

Allright thats starting to set a bulb off for me. Now I would think you have to regulate the actual pressures to both sides and I cant see how a Needle valve will do that. dont we need to use pressure regulators and not air dampers? I would think no mater how big or small the opening in the needle valve its gonna get max pressure through it in the end . Yes no?

A pressure regulator does work a bit better. How are you trying to open it with air on the top of the wastegate? The wastegates have rather light springs so it takes very little to open them without air.

A pressure regulator does work a bit better. How are you trying to open it with air on the top of the wastegate? The wastegates have rather light springs so it takes very little to open them without air.

I used compressed air on the top then the bottom then both and watched how it functions. I can only get it to open by putting compressed air on the bottom.
Im wondering what the math is if I put 50 psi boost on the bottom and 25 psi on the top it will open but not put as much pressure on the diaphram? posebly 25 psi and not 50? so in essence I could use two Home depot boost pressure regs and have the WG (BOV. lol) open @ 50 psi
Hmm id have to put a pressure regulator on the top set to 25 right? and a HomeDepot boost controller set at 50 on the bottom? shoot it think Im getting it :o: Btw its the Tial sport WG if that helps Its a used MPI kit I got from 02Bigstrokin using a GT45.

Umm I just put head studs in my LB7 in the Blazer and put my SC5 6 speed w a vert setup for twins. How much boost is too much and whats safe?

BTW thanks for the info :popcorn:

Can u pm a part # for the air filter? its an afe? he didnt send me an air filter, hmm maybee a price to